LETTER
Facile Preparation of Diaryl- and Dibenzylfuranones
1749
References and Notes
(7) Representative Experimental Procedure.
To a flame-dried flask (under an argon atmosphere) charged
with benzyl bromide (226 mg, 1.33 mmol), PdCl (PPh ) (5
(
1) (a) Richecœur, A. M. E.; Sweeney, J. Tetrahedron 2000, 56,
89. (b) Hollingworth, G. J.; Richecœur, A. M. E.; Sweeney,
J. J. Chem. Soc., Perkin Trans. 1 1996, 2833.
c) Hollingworth, G. J.; Perkins, G.; Sweeney, J. J. Chem.
2
3 2
3
mol%), AsPh (8 mol%) and CuI (8 mol%) was added THF
3
(5.0 mL) and the mixture warmed to 50 °C. 3,4-Bis(tributyl-
(
stannyl)furan-2(5H)-one (450 mg, 0.66 mmol) in THF (5.0
mL) was added dropwise via syringe. After reaction was
complete the mixture was concentrated under reduced
pressure. Purification via flash chromatography (silica gel,
PE–Et O 1:1; R = 0.50) gave 3,4-dibenzylfuranone as a
Soc., Perkin Trans. 1 1996, 1913.
(2) Carter, N. B.; Mabon, R.; Richecœur, A. M. E.; Sweeney, J.
B. Tetrahedron 2002, 58, 9117.
(
3) For other routes to 3,4-disubstituted furanones, see, for
instance: (a) Rossi, R.; Bellina, F.; Raugei, E. Synlett 2000,
2
f
clear colorless oil (78 mg, 45%). IR (CHCl ): 3063, 1754,
3
1749. (b) Forgione, P.; Wilson, P. D.; Fallis, A. G.
–1 1
1
3
668 cm . H NMR (250 MHz, CDCl ): d = 3.71 (2 H, s),
.74 (2 H, s), 4.51 (2 H, s), 6.99–7.02 (2 H, dd, J = 7.0, 2.0
Hz), 7.22–7.29 (8 H, m). C NMR (60 MHz, CDCl ): d =
0.0, 34.0, 71.7, 127.0, 127.2, 127.7, 129.0, 129.1, 129.2,
3
Tetrahedron Lett. 2000, 41, 17. (c) Duboudin, J. G.;
Jousseaume, B. J. Organomet. Chem. 1979, 168, 233.
13
3
(
(
(
d) Mornet, R.; Gouin, L. Bull. Soc. Chim. Fr. 1977, 737.
e) Crisp, G. T.; Meyer, A. G. J. Org. Chem. 1992, 57, 6972.
f) Wakharkar, R. D.; Deshpande, V. H.; Landge, A. B.;
3
1
29.5, 136.3, 138.5, 160.3, 175.2. MS (CI, NH ): m/z calcd
3
+
for C H O : 265.1231. Found [MH] : 265.1221; m/z (%) =
1
8
16
2
Upadhye, B. K. Synth. Commun. 1987, 17, 1513.
g) Okazaki, R.; Negishi, Y.; Inamoto, N. J. Org. Chem.
989, 49, 3819. (h) Delaunay, J.; Orliac-Le Moing, A.;
2
19 (20), 91 (25).
8) For racemic and asymmetric syntheses of hinokinin, see:
a) Morimoto, T.; Nagai, H.; Achiwa, K. Synth. Commun.
005, 35, 857. (b) da Silva, R.; de Souza, G. H. B.; da Silva,
(
1
(
(
2
Simonet, J. Tetrahedron 1988, 44, 3819. (i) Boukouvalas,
J.; Maltais, F.; Lachance, N. Tetrahedron Lett. 1994, 35,
A. A.; de Souza, V. A.; Pereira, A. C.; Royo, V. D.; Silva,
M. L. A. E.; Donate, P. M.; Araujo, A. L. S. D.; Carvalho, J.
C. T.; Bastos, J. K. Bioorg. Med. Chem. Lett. 2005, 15,
7897; and references therein.
(
(
4) It is not possible to directly discern the yields of the
individual coupling reactions: assuming a maximum yield of
1033. (c) Bennett, D. J.; Pickering, P. L.; Simpkins, N. S.
100% for the second coupling (normally a more efficient
Chem. Commun. 2004, 1392. (d) Xia, Y. M.; Liang, Q. R.;
Wang, X. L.; Cao, X. P.; Pan, X. F. Chin. J. Chem. 2003, 21,
process, see ref. 2), the maximum possible yield for the first
step is 51%. Our original observations in monocoupling of 1
with PhI gave 2 (Ar = Ph) in a yield of 51%.
1540. (e) Enders, D.; Lausberg, V.; Del Signore, G.; Berner,
O. M. Synthesis 2002, 515. (f) Brinksma, J.; van der Deen,
H.; van Oeveren, A.; Feringa, B. L. J. Chem. Soc., Perkin
Trans. 1 1998, 4159; and references therein.
5) Representative Experimental Procedure.
To a flame-dried flask (under argon atmosphere) charged
with PdCl (PPh ) (2 mol%), CuI (8 mol%), AsPh (8 mol%)
2
3 2
3
(9) Data for (±)-Hinokinin.
was added 3,4-bis(tributylstannyl)furan-2(5H)-one (500 mg,
.76 mmol) as a solution in dry, deoxygenated DMF,
–1 1
IR (CHCl ): 1769, 1495, 1245, 1033 cm . H NMR (400
3
0
MHz, CDCl ): d = 2.45–2.60 (3 H, m, ArCH CH, ArCH CH
3
2
2
followed by iodobenzene (310 mg, 1.52 mmol), also added
dropwise as a solution in DMF (2.0 mL). After reaction was
complete (24 h) the mixture was diluted with aq KF (1 M,
and ArCH2CHCHC=O), 2.86 (1 H, dd, J = 14.5, 7.0 Hz,
ArCH CHC=O), 2.99 (1 H, dd, J = 14.0, 5.0 Hz,
2
ArCH CHC=O), 3.87 (1 H, dd, J = 9.00, 7.00 Hz, OCH ),
2
2
1
0.0 mL) and extracted with Et O (3 × 30.0 mL), washed
2
4.14 (1 H, dd, J = 10.0, 7.00 Hz, OCH ), 5.95 (4 H, m,
2
with H O (3 × 15.0 mL) and brine (3 × 15.0 mL). Solvent
2
OCH O), 6.46–4.48 (2 H, m, 2 × Ar,), 6.62 (2 H, m, 2 × Ar),
2
was removed under reduced pressure and the crude product
was purified via flash chromatography (silica gel, 3:2 PE–
Et O; R = 0.24). Recrystallization (CH Cl –PE) gave 3,4-
13
6
3
.64 (2 H, m, 2 × Ar). C NMR (100 MHz, CDCl ): d = 35.2,
8.8 (ArCH ), 41.7 (ArCH CHCHC=O), 46.9
3
2
2
2
f
2
2
(ArCH CHCHC=O), 71.6 (OCH ), 101.4 (OCH O) 108.6,
2
2
2
diphenylfuran-2(5H)-one as pale yellow crystals (56%, 101
108.9, 109.2, 109.8, 121.9, 122.6, 131.7, 132.0, 132.1,
mg); mp 104–105 °C (CH Cl –PE). IR (CHCl ): 1751, 1646,
2
2
3
146.8, 146.9, 148.3 (2 × Ar), 178.8 (C=O). MS (CI, NH ):
m/z calcd for C H O : 355.1181. Found [MH] : 355.1164;
20 19 6
m/z (%) = 135 (45).
3
–
1 1
1
7
(
489 cm . H NMR (250 MHz, CDCl ): d = 5.10 (2 H, s),
+
3
1
3
.23–7.33 (10 H, m). C NMR (60 MHz, CDCl ): d = 71.0
OCH ), 126.6, 127.9, 129.2, 129.3, 129.4, 129.7, 130.6,
3
2
(10) (a) Leutenegger, U.; Madin, A.; Pfaltz, A. Angew. Chem.,
Int. Ed. Engl. 1989, 28, 60. (b) von Matt, P.; Pfaltz, A.
Tetrahedron: Asymmetry 1991, 2, 691. (c) Moritani, Y.;
Appella, D. H.; Jurkauskas, V.; Buchwald, S. L. J. Am.
Chem. Soc. 2000, 122, 6797. (d) Yun, J.; Buchwald, S. L.
Org. Lett. 2001, 3, 1129. (e) Jurkauskas, V.; Buchwald, S.
L. J. Am. Chem. Soc. 2002, 124, 2892. (f) Appella, D. H.;
Moritani, Y.; Shintani, R.; Ferreira, E. M.; Buchwald, S. L.
J. Am. Chem. Soc. 1999, 121, 9473.
1
31.0, 131.2, 156.6, 173.9. MS (CI, NH ): m/z calcd for
3
+
C H O : 237.0916. Found [MH] : 237.0915; m/z (%) =
16
13
2
179.0 (15).
(
6) See, for instance: (a) Higuchi, K.; Sawada, K.; Nambu, H.;
Shogaki, T.; Kita, Y. Org. Lett. 2003, 5, 3703. (b) Wang,
L.; Pan, Y.; Jiang, X.; Hu, H. Tetrahedron Lett. 2000, 41,
7
(
25. (c) Kumar, P. Org. Prep. Proced. Int. 1997, 29, 477.
d) Pan, Y.; Zhang, Z.; Hu, H. Synthesis 1995, 245. (e) Pan,
Y.; Zang, Z.; Hu, H. Synth. Commun. 1992, 22, 2019.
f) Hashem, M. A.; Weyerstahl, P. Tetrahedron 1984, 40,
(
2003. (g) Heck, R. F.; Nolley, J. P. Jr. J. Org. Chem. 1972,
37, 2320.
Synlett 2006, No. 11, 1747–1749 © Thieme Stuttgart · New York